Currently, the most common form of short distance wireless communication between a personal computer ("PC") and a wireless communication enabled electronic device is infrared ("IR) communication. IR communication, however, has shortcomings in being a very short distance communication technique (typically a few meters at best) and requires an uninterrupted line of sight between RF ports on both devices. Both of the limitations associated with IR communication are problematic in the modern world of portable electronic devices.
Another form of wireless communication is radio frequency ("RF") communication. Some legacy type architecture computers incorporate an IR port and circuitry to support IR communication. For short distance wireless applications, a legacy type computer can be combined with a portable phone (of the type used for short distance communication around the home or office--a traditional cellular phone is not acceptable for this purpose due to power, frequency and operational expense requirements) via a cable or direct connection to give the computer the ability to communicate with another electronic device (typically another computer) via RF communication from the portable phone to a receiver spaced a short distance away. FIG. 1 illustrates a prior art embodiment of a legacy architecture portable computer 10 that is coupled via a cable 12 to a portable telephone 14, as required by such a system. Portable telephone 14 provides RF transceiver functionality for portable computer 10. FIG. 2 illustrates another prior art embodiment of a short distance RF communication system in which a legacy architecture portable computer 10 is coupled via a data cable 12 to a dedicated short distance RF communication module or device 16 (i.e., which is able to transmit and receive RF signals over a short distance--e.g., up to 10 meters). RF module or device 16 has an antenna 18 and RF circuitry 20 (typically transceiver functionality) coupled to antenna 18. In both of the systems disclosed in FIGS. 1 and 2, there are two electronic apparatus and a coupling cable that a user must keep together.
In addition to the above, portable computer 10, portable phone 14 and RF module or device 16 (as well as all electronic devices) each require a power source for proper operation. While one or more of these devices may derive its power solely from batteries, the more common and practical practice is to have each device derive its power from batteries while the device is in a portable mode and from a power cord coupled to a conventional power supply when the device is near a permanent power supply. FIGS. 3 and 4 illustrate the systems of FIGS. 1 and 2, respectively, in which portable computer 10, portable phone 14 and RF device 16 obtain their power from a power cord 22 coupled to a conventional power supply 24 (such as a power receptacle--for example, 110 VAC). Devices having an input voltage requirement less than the supply voltage may also have a step down transformer or voltage reducing circuit 26. For example, a transformer or other voltage conversion or regulator circuitry may be used to reduce a supply voltage of 110 VAC, supplied by a power receptacle on a wall, to the required input voltage of the device. For devices requiring DC voltage, an AC/DC converter may also coupled between the step down transformer and the device.
Whether obtaining power solely from batteries, or from batteries only when no conventional power supply is available, the batteries will eventually run down and require replacement unless the batteries are of the rechargeable type and are recharged separately or while the device of which the batteries are a part is coupled to a conventional power supply. Rechargeable batteries may be recharged in one of three methods. First, batteries 28 within a portable electronic device may be physically removed from the device and placed in a battery recharge mechanism 30 until recharged, as illustrated in FIG. 5. The batteries are replaced in the electronic device after being recharged. Second, batteries 28 may be recharged within the electronic device it powers (in this case portable computer 10, portable telephone 14 or RF device 16) via a power cord 22 (typically having a transformer 26 at one end of the power cord--typically the portion that plugs into the power source) coupling the portable electronic device to a conventional power supply 24, as discussed above and illustrated in FIGS. 3 and 4. Third, batteries within small portable electronic devices, such as portable phone 14 may also be recharged within the device while the device is placed within a cradle or receptacle 32 that is coupled, via a power cord 22, to a conventional power supply 24, as illustrated in FIG. 6.
Removing a device's batteries for recharging (as shown in FIG. 5) is awkward and burdensome. The electronic device using the batteries is typically unusable--if of the battery only type--while its batteries are removed. There is also the potential problem of losing or damaging the batteries and/or the device itself through mishandling of the device or batteries and wear resulting from the continual process of removing and replacing batteries. If the device is of the type allowing operation from a power cord only, the mobility of the device is limited to the length of the power cord. The method of recharging batteries shown in FIGS. 3 and 4 is more convenient than the method of FIG. 5 in that the batteries are not removed from the device while recharging, which facilitates immediate operation of the device, even if the batteries are not fully charged. For devices small enough, the recharging cradle is the most convenient method of recharging. One disadvantage of the charging cradles of the prior art is that they require a power cable coupling the charging cradle to a dedicated power source, such as a 110 VAC wall outlet or 12 VDC outlet (such as an automotive cirgarette lighter power supply). Such recharging techniques are useless in situations where there are no, or insufficient, discrete power sources available to plug in the power cord of the charging cable.
FIG. 7 illustrates a cradle 34 adapted to supply both power and data to an electronic device 14. In one embodiment, shown in FIG. 8, cradle 34 has both a connector for power 36 and a data connector 38. In another embodiment, shown in FIG. 9, cradle 34 has a single power and data connector 40 for coupling power (via cable 22) and data (via cable 12) to the portable phone 14.
Combining the RF communication and power requirements, it soon becomes apparent that a user of any one of the previously described communication systems will need a portable computer 10, a power cord 22 for supplying external power to computer 10, a portable phone 14 or RF module 16, a power cable 22 for supplying external power to portable phone 14 or RF module 16, and a data cable 14 for coupling portable computer 10 to portable telephone 14 or RF module 16--for a total of two electronic devices, two power cords and a data cable. For the recharging cradle embodiments--a total of three electronic devices, two power cords and a data cable are required.